Transcript How is Biosecurity Achieved? - MVDr.Josef Holejšovský,Ph.D.

Capacity building of the competent authorities for food safety, veterinary and
phytosanitary policy
EuropeAid/132281/D/SER/MK
Training course
L e c t u r e r : MVDr. Josef Holejšovský PhD
Place: Skopie, FYROM
Date: 18-22 May 2015
Capacity building of the competent authorities for food safety, veterinary and
phytosanitary policy
EuropeAid/132281/D/SER/MK
Content:
Title B:General bio security
measures on farm, with emphasis on
pig and poultry farms
Some Epidemiological Aspests
Communicable diseases
Noninfectious and
Noncontagious Dis. e.g.:
- Infestations exclusively
transm. by vectors (Filaria, etc)
Infectious and
Contagious dis. e.g.:
- Rabies,
- Brucelosis
- FMD, ASF, CSF, HPAI, ND,
- Genetic diseases etc.
Infectious,
not contagious dis. e.g.:
Contagious dis.e.g.:
- Arborviroses - Horse sickness - Scabies,
- Strongyloidiosis,
- Blue tongue
- Fasciolosis
Some Epidemiological Aspests
SIX ESSENTIAL ELEMENTS OF INFECTIOUS DISEASE
Infectious agent
Reservoir
Susceptible host
Portal of exit
Mode of transmission
Portal of entry
Some Epidemiological Aspests
The setting for a infectious disease situation
Pathogen
Environment
Factors influencing disease transmission
Environment
Agent
• Weather
• Housing
• Geography
• Occupational
• setting
• Air quality
• Food
• Infectivity
• Pathogenicity
• Virulence
• Immunogenicity
• Antigenic stability
• Survival
Host
• Age
• Sex
• Genotype
• Behaviour
• Nutritional status
• Health status
Chain of Transmission
Animal to
Animal
transmission
Reservoir
Portal of exit
Susceptible Host
Portal of entry
Agent
Mode of transmission
NATcURAL COURSE OF DISEASE
Usual Time
of Diagnosis
Pathologic Onset of
Exposure Changes Symptoms
Stage of
Susceptibility
Stage of
Subclinical Disease
PRIMARY PREVENTION
Stage of
Stage of Recovery
Clinical Disease Disability or Death
SECONDARY PREVENTION
Incubation Period
TERTIARY PREVENTION
Prevention – better than cure
Primary prevention: removing the determinants or risk factors of
diseases: Ban on feed of ruminants with animal proteins, Ban on
import of animals from countries or regions not free from
dangerous infectious diseases (e.g.: exotic FMD, ASF etc)
Secondary prevention: aims to early detect diseased individuals
in order that the progression of the disease can be halted: e.g.
early detection of outbreaks to avoid onset of secondary cases
(important especially for diseases that can go unnoticed).
Stamping out of highly contagious diseases
Tertiary prevention: main scope is to reduce distress from
diseases for which treatment is not effective, is often difficult to
distinguish from therapeutic intervention
Prevention and control aspects
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Desinfection - physical methods
- chemical methods
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Chemotherapy & Chemoprophylaxis
- sulphonamids, etc
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Improved management systems - biosecurity
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Control of insect vectors or
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Wildlife reservoirs – mammals, birds - know the
epidemiological situation within the populations
Are additional measures which may be used.
Prevention and control aspects
• The physical methods available for inactivating
infectious agents include:
– heat (moist or dry),
– ultraviolet light and
– irradiation.
• Thermal inactivation - most widely used physical
methods
•
However, there is wide variation in the
susceptibility of infectious agents to thermal
inactivation.
Prevention and control aspects
• Thermal inactivation
• Most vegetative bacteria and many viruses are
rapidly inactivated at 100°C.
• FMD virus as well as many other viruses can survive a temperature of
95°C for 15 seconds but is reliably inactivated at 148°C in 3 seconds.
• Bacterial endospores - a temperature of 121°C for 15 minutes is
required for the destruction of.
• Prions - highly resistant to chemical disinfectants and to heat:
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Autoclaving (moist heat) at 121°C for up to 5 hours
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Rendering parameters: 133 °C, 3 bars, 20 minutes
Prevention and control of animal diseases
• Chemical desinfection
• Mycoplasmas, Eenveloped viruses, Gram positive and
Gram negative bacteria are susceptible to the most
chemical disinfectants;
• Non enveloped viruses and Acid fast bacteria
(Mycobacterium..) are moderately resistant,
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c
• Bacterial endospores and Coccidial oocysts are highly
resistant to chemical compounds.
• Prions are extremely resistant to chemical inactivation
Prevention and control of animal diseases
• Safe thorough cleaning is the first step in a
disinfection programme and this measure alone will
remove most of the infectious agents from equipment or
from a building.
• Chemical compounds are used to
– destroy residual infectivity, especially in inaccessible
locations and also to
– render a building before cleaning when dealing with
zoonotic diseases such as anthrax
General Biosecurity
• Definition:
• Biosecurity is the implementation of measures that
reduce the risk of the introduction and spread of disease
agents. It requires the adoption of a set of attitudes and
behaviors by people to reduce risk in all activities
involving domestic, captive/exotic and wild animals and
their products”
• Biosecurity is the management of risks to the economy,
the environment, and the community, of pests and
diseases entering, emerging, establishing or spreading.
• Biosecurity can be implemented off-shore, at the border
and on-farm.
Biosecurity components
• Increase the animal's ability to resist disease;
• Eliminate sources of the infectious agent ;
• Minimize the number of contacts that might
result in disease;
• The key to good biosecurity is reducing and
controlling the movements of people, vehicles
or equipment into areas where your farm
animals are kept.
General Biosecurity
The Benefits of Biosecurity
•Helps keep out diseases
•Reduces the risks
•Limits the spread of disease
•Improves overall health of the animals
•Reduces mortality losses
•Improves profitability
Farm Biosecurity
• Farm biosecurity is a set of measures designed to
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protect a property from the entry and spread of
pests, diseases and weeds.
Farm biosecurity is the farmer´s responsibility, and
that of every person visiting or working on farmer´s
property.
The most important measures to be takenat farm:
control of entry (check and evidence) of all persons
control of entry of animals
Control (check and evidence) of entry of vehicules
Farm Biosecurity
Where the farmer has been?
•Farmer may be his own biggest risk
•Designated clothes and boots for the poultry / pigs
houses
•How clean are the floor boards of the trucks?
•Have you been near birds (hunting, farm ponds, pet
stores, zoos, parks)
Biosecurity
• Where do destructive diseases come from ?
Sources:
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7.
Bought-in pigs from auctions, speculators;
People: neighbours, family, friends, reps.
officials, vets;
Swill, especially if it includes animal tissues;
Vehicles from millers, butchers, dealers;
Containers, especially second-hand feed sacks;
Birds, dogs, rodents;
Water, dust, wind
Biosecurity
How Disease is Spread
•People
•Vehicles
•Equipment
•Disease Animals
•Carrier Animals
•Fecal Material
•Body Discharges
•Contaminated Feed and Water
Other routes of pathogen transmission
Aerosol
• Pathogens can be transmitted by air, sometimes surprisingly
long distances.
• The efficacy of airborne transmission strongly depends on
geographical and climatic conditions.
•
It also depends on virus load being emitted from the source
herd, which is proportional its size and numbers animals
present.
• The resistance of the pathogen to drying and sunlight
determines its ability to spread through the air
Routes of pathogen transmission
Fomites (mechanical transmission)
• Vehicles, especially those used for transporting pigs, are
also efficient vectors of pathogens and need due care.
•
Birds, insects, rodents and other pest are known to
transport pathogens
• Pandemic H1N1 doesn’t survive long in environment
• Role of wild birds in transmission is unknown, not proved
Vehicular Traffic
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Feed, Livestock & Service trucks
Perimeter fencing
Disinfecting stations
Load outs (incoming vs outgoing)
Bulk bin access
Drivers
• boots, coveralls,
Biosecurity and services
• Veterinarians , insemination technicians..
– possibility to wash and change clothes, boots….
– for high top pig breeding herds farmer want to
know the clients of vet and other servicemen
The routes of Disease transmission
People
• It is clear that humans can transport the pathogens on
boots, clothes, and hands.
– Entry decontamination protocols
– Hand wash (shower) change of clothes
• Farm workers must not own pigs at home
• Thieves are a problem, not just because they steal pigs
or equipment, but also because they may not stop to
read the biosecurity protocols first)
Biosecurity
Rodents, Animals and Insects
• The only animal that needs to be in a chicken
house is a chicken, in a pig house is a pig
• Active rodent control (bait stations and fresh
bait)
• Clean up spilled grain and feed
• Keep dogs and cats out of the pig and poultry
houses
• Insects carry disease,
• Birds carry disease as well
How is Biosecurity Achieved?
• Outside Perimeter
– High fences prevent intruders such as animals
and people from entering the premises and
possibly transmitting diseases to the flock.
How is Biosecurity Achieved?
• Bait Stations
– Reduces the risk of rodents, which are small
enough to easily get into facilities and carry many
pathogens, from infecting the flock.
How is Biosecurity achieved?
• Sanitation of Equipment and Supplies
– The purpose of sanitizing equipment, surfaces,
and supplies is to reduce pathogens.
• This is especially important in preventing the
spread of diseases between neighboring
flocks.
How is Biosecurity achieved?
• Good Hygiene
– Prior to entering the facility, employees and visitors
should demonstrate good hygiene by showering and
wearing clean designated clothing such as boot covers,
hairnets, and cover-als.
How is Biosecurity achieved?
• Footbaths
– Footbaths are placed outside the door of all
facilities and contain disinfectants, reducing the
risk of bringing pathogens inside the buildings.
Biosecurity in poultry farm
Foccused on HPAI
Water fowls and migratory birds
are the most potential agents to transmit the HPAI virus.
These birds if infected do not get ill but they are healthy carriers
and shed virus through their feces (droppings) and other body secretions.
Mechanisms of
Influenza Virus Antigenic “Shift”
Non-human
virus
Human
virus
Reassortant
virus
The ducks are being raised outside. They are free to comingle with migratory birds.
This poses a huge biosecurity risk. The barn in the picture is full of hogs. The manure
from the hogs is running out to where the ducks are living. This poses a risk as the
hogs, biologically, serve as a mixing vessel for disease organisms, which makes genetic
mutation much easier, ultimately contributing to the risk of a human pandemic.
PIGS
HOG MANURE
Biosecurity
Mortality !
•Be aware of changes in mortality patterns
•Observe the birds
•Collect dead birds frequently
•Dispose of them in a proper way
•A pile of rotting birds is not composting: make sure
adequate temperature is reached
•Keep animals out of the composter
Know the Warning Signs
of Infectious Bird Diseases
• Sudden increase in bird deaths in your flock.
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Lack of energy and poor appetite.
Sneezing, gasping for air,coughing, nasal discharge
Watery and green diarrhea.
Swelling around the eyes, neck, and head.
Tremors, drooping wings, circling, twisting of the head
and neck, or lack of movement (ND)
Early detection is important to
prevent the spread of disease.
Transmission to humans
• Close contact with infected birds and
through aerosols, discharges and surfaces
• Virus is excreted in feces, which dries,
pulverized and inhaled
• Flapping of wings hasten transmission
Stages of Avian and Pandemic Preparedness
Stage 1: Avian influenza-free country
Stage 2: Avian influenza in domestic fowl
Stage 3: Avian influenza from poultry to
humans
Stage 4 - Human-to-human transmission
(pandemic influenza) in the country
Stage 1: Keeping Country Bird
Flu Free
Prevention of entry of the virus:
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Ban of all poultry and poultry products from AIinfected countries
Border control
Ban on sale, keeping in captivity of wild birds
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Biosecurity measures
Standardized footbath
Confiscation and destruction of unlicensed cargo
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Surveillance of Poultry in Critical Areas
Influenza vaccination for all poultry workers,
handlers
STAGE 2: Avian Influenza in Domestic
Fowl
Individuals at risk
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Poultry handlers/workers
Sellers/ people in live chicken sale
Aviary workers/ Ornithologists
Cullers
People living near poultry farms
Any individual in close contact with infected
birds
STAGE 2: Avian Influenza in
Domestic Fowl
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Prevention of spread from birds-to birds:
early recognition and reporting, mass culling,
quarantine of affected area
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Prevention of spread from birds to humans:
human protection through proper handling of
infected birds, use of protective gear by
residents, poultry handlers, and response
teams
STAGE 2: Avian Influenza in Domestic
Fowl
Response to sick or dead birds
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Protection of exposed residents – gloves/ plastic
material in handling sick or dead birds, hand washing
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Personal protective equipment for cullers – caps,
masks, goggles, gowns
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Identification of exposed individuals and quarantine
for 7 days
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Reporting to the Health Emergency Response Team/
local health officer
STAGE 3- Avian Influenza in Humans
Community response
• Patient: face mask, in a separate area or at
least 1 meter distance from other people
• Monitoring of contacts of the case
• Protection of caregiver : face mask and
goggles or eye glasses, hand washing, selfmonitoring for signs and symptoms
• Immediate transfer to the Referral Hospital
• Protection of the transporting team and
disinfection of vehicle
Strategic Approaches
Use of antiviral agents
• Infection control
• Quarantine of contacts
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Import ban
Border control
Wildlife Act
Early recognition/
reporting
• Mass culling,
• Quarantine of
affected area
• Management of
public panic
• Early recognition/
reporting
• Proper handling
of birds
• Protective gear
• Management of
public panic
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Passenger entry-exit
management
Border control
Quarantine of
contacts
Isolation
Management of cases
Social distancing
Personal hygiene
Management of
public panic
Biosecurity
Foccused on pig farms
The routes of Disease
transmission
• Pigs
– Most frequently diseases move with infected pigs
– Do not move sick pigs
But
– Pigs incubating the disease may not be clinically
ill yet
– Recovered pigs may appear healthy but can
spread disease
Action points
• Inspect pigs before moving
• Use test to detect disease
– Antibody tests for previous exposure
• elisa
– Antigen for incubating disease
• PCR
• Quarantine incoming pigs
The Infection of Pigs with
“Zoonotic” Salmonella spp.
There are 3 mechanisms of the Salmonella
infection at herd level:
1) The horizontal transmission of Salmonella
spp.
from the environment into the herd
2) The vertical transmission: Sow
piglet
weaner, weaner
piglet,
market pig
3) The permanent infection-contamination
infection cycle = “on-farm perpetuation”
The Infection of Pigs with
“Zoonotic” Salmonella spp.
The consequences of the multiple sources and
the “on-farm perpetuation”:
• There is no general infection pattern: each herd
(farm) has an “own” infection pattern
• This means that before taking action on a
positive farm, it is necessary to identify the
“farm-own” infection pattern to concentrate
on the the “hot spots” of the sources and the
perpetuation
Capacity building of the competent authorities for food safety, veterinary and
phytosanitary policy
EuropeAid/132281/D/SER/MK
Capacity building of the competent authorities for food safety, veterinary and
phytosanitary policy
EuropeAid/132281/D/SER/MK
C O N TA C T S :
Name of the Expert: HOLEJŠOVSKY
Josef, DVM, PhD
E- mail: [email protected]